MTS - Mohr Tranebjaerg Syndrom
Mohr–Tranebjærg syndrome (MTS) is a rare X-liked recessive syndrome also known as Deafness-dystonia syndrome and caused by mutation in the TIMM8A gene causing neurodegenerative processes.
The clinical course strikes us as being still vague (after reading many scientific articles).
The only thing that all affected persons have in common is that they progress to severe deafness till the age of 2 in a gradual process that is hardly detectable as it is not a "normal" inner ear hearing loss but - as to our knowledge - always a neural hearing loss, e.g. a auditory neuropathy. This kind of disorder cannot be detected by a conventional hearing test. Reliable results without the childs cooperation can only be obtained with a BERA test (brainstem electric response audiometry).
Finally a cochlear implant can be helpful but only if the hearing impairment has been detected in time. Our younger son has been provided with CIs on both sides. But we still worry whether the auditory nerve will stay intact or may regress in the course of the disease.
In the early childhood behavioral problems along with lack of impulse control and paranoia can occur as well as (mild) mental deterioration.
In puberty the chilldren can develop various movement disorders, like dystonia or ataxia mostly together with active tendon reflexes, ankle clonus and a positive Babinski.
The susceptibility to infections can increase, recurrent infections occur (but only if the BTK-gene located in the Xq22 region is affected). This is not the case with our sons (TIMM8A-gene defect) but still both suffer from a quite increased susceptibility to infections (but limited to ENT infections).
Later on - in late adolescence/as youngsters - reduced visual acuity, photophobia, acquired color vision deficiency and a central skotoma can be developed.
From the age of 40 dementia symptoms may occur (as to scientific articles).
For more information on our sons select menue item "experiences".